Pipe-wrench



G. C. LAWSON- PIPE WRENCH.

APPupAnon FILED MAY I0. 1920.

1,362,014. Pat nted D c- 14, 1920.

INVENTOR ATTORNEY UNITED STATES;

GOTTFRID C. LAWSON, .OF CLEVELA ND, OH IO.

PIPE-wnENcHL To all whom it may concern:

Be it known that I, Go'r'rrnm G. LAWSON, a citizen of the United States, residing at Cleveland, in the countyof Cuyahoga and State of Ohio, have invented certain new and useful Improvements in Pipe-Wrenches. of which the following is a specification.

This invention relates to wrenches, and particularly to pipe wrenches of the adjustable jaw type, the outer jaw being adj ustablc and the inner jaw being rigid or integral with the handle.

The object of the invention is to provide an improved wrench in which the outer jaw will have a free rocking movement to take hold of and release the pipe, a fulcrum be ing provided in the head of the wrench on which the adjustable jaw rocks, this ful crum being located in particular relation to the depth of the jaws, in order to get a good hold on a large sized pipe and to release freely without binding when the pressure of the handle is released.

The axis of the handle is placed at a particular and convenient an le to the axis of the jaws, in order to provi e for most effective operation in narrow spaces. A further object of the invention is to provide improved means for holding the adjusting nut in desired position, so that the adjustment of the outer jaw will not change during use. Various other features of improvement will be apparent from the following description.

In the accompanying drawings Figure 1 is a plan of the wrench. Fig. 2 is a longitudinal section. Fig. 3 is a cross section on the line 3-3 of Fig. 2. Fig. 4 is a detail of a s ring.

eferring specifically to the drawings, 6 indicates the handle of the wrench, terminated at its front end in a head 7 provided with a fixed jaw 8 which is presented at a slight inclination to a perpendicular from the axis of the handle, so that the two jaws will have an angle of about 115, to said axis, as it has been found that this angle is a most convenient one for operating the wrench, and gives a wider ran e of use in a smaller space than other ang es. The head is slotted lengthwise to receive the shank 9 of the outer adjustable jaw 10, the axis of said shank being perpendicular to the face of said jaw. The shank has racks 11 at its front and rear edges, and these racks are engaged by a ring nut 12 set in a cross recess or slot 13 in the head. A flat Specification of Letters Patent.

Patented Dec. 14, 1920.

Application and May 10, 1920. Serial no. 350,101.

spring 14 bears against the edge of the shank near the inner end thereof and normally holds the jaw in open position. Within the ring nut 12, at each side of the shank 9 is a C-spring 15, the back of which bears against the inner surface of the nut and the ends which bear against the sides of the shank, these ends being bent inwardly as shown at 16. The pressure of these springs between the parts by which they are confined is sufiicient to prevent accidental movement of the nut, and permits the nut to be turned for adjustment when desired.

The shape of the slot through the head is peculiar, and is of importance. At its front end the slot is flared or widened as indicated at 17, in the plane of the jaws, and at its rear end it is also widened, as indicated at 18. in the same plane, The widened part 17 at the front end is located at the front side, or the side toward the jaws, while the widened part 18 is located on the opposite side of the shank, and the surface 19, opposite the widened part 17 and the surface 20, opposite the widened part 18, are substan tially parallel to each other, or at very slight angle to each other. This structure in connection with .the cross slot 13 produces a fulcrum point or shoulder at 21 on which the shank rocks, said fulcrum point being close to or against the nut 12. The cross slot 13 in which the nut works, tapers in a plane parallel to the plane of the jaws; i. 0., this slot is somewhat wider at the back side of the wrench than at the front, whereby the nut can rock while retaining, however, its contact with the shoulder or point at 21.

This construction has been found most advantageous for the operation of the wrench, particularly when extended to full size. There is no looseness permittin the wrench to enlarge after it is adjuste but still the nut and the adjustable 'aw can rock on the fulcrum to take hold 0 and release from the work. When the nut is set for adjustment it works against the shoulder 21, and when applied to the work will rock under pressure to grip the work, the front end of the shank swinging down in the enlarged art 17 of the longitudinal slot until fina ly it comes in contact with the head, with the nut in contact at front and back with the front surface of the cross slot 13, which makes a very rigid structure, the shank rocking on the shoulder 21 as a fulcrum. When the pressure is released the flat spring 14 rocks the adjustable jaw the other way and quickly releases the grip. The function of the C-springs 15 in holding the nut at adjustment has been previously referred to.

The invention is not limited to the exact form shown, but modifications may be made within the scope of the following claims.

1' claim:

1. A wrench having a slotted fixed jaw and handle, an adjustable jaw having a rack shank in said slot, a ring nut engaging the rack of the shank, and a pair of C-springs confined in the nut and bearing at their ends against opposite sides of the shank respectively.

2. A wrench having a slotted fixed jaw and handle, an adjustable jaw having a rack shank in said slot, a ring nut engaging the rack of the shank, and a pair of C-springs confined in the nut and hearing at their ends against opposite sides of the shank respectlvely, the backs of the springs bearing against the inside of the nut and the ends of the springs being bent inwardly where they bear against the shank.

In testimony whereof, I do afiix my signature in presence of two witnesses.

GOTTFRID C. LAWSON.

Witnesses:

JOHN A BOMMHARDT, ROBERTSON BOWIE. 

